In our study, the downregulated genes associated with TAO were identified as PLP2, CCL4, CCL4L1, CCL4L2, EGR1, RPL9, LAMP2, PRKACA, TOP2B, DGKZ, ANPEP, TCIRG1, NDUFA1, HBB, and RPL32. This evidence concerns the gene NDUFA1 and thromboangiitis obliterans.